CO2 Emission Reduction Potential andTechnological Aspects of the Oxyfuel Technology in Cement Clinker Production

Dr.-Ing. Volker Hoenig, Dipl.-Ing. Kristina KoringOCC3 Ponferrada September 2013OCC3, Ponferrada, September 2013

AGENDA

1 Clinker burning process

2 Integration of the Oxyfuel Technology and design aspects

3 I t l t ti3 Impact on plant operation

4 Impact on material conversion and product quality

5 Cost estimation

6 Summary and Outlook

1. Introduction - Clinker burning process

Flue gas300 - 350 °C Material CO

Raw meal

Cyclone

300 350 C Material CO2

Fuel CO2CaCO3, SiO2, Al2O3, Fe2O3

Cyclonepreheater

Calciner

Cooler exhaust air

Tertiary air ductFuel/air

Fuel

700 - 1000 °C

200 °C - 350 °C

850 °C

700 - 1000 °C

Cooling air

Rotary kiln 2000 °C

700 1000 C

Clinker

CaCO3 CaO + CO2

Coolerg Clinker

2. General layoutHeat

exchangerBag filter

CO2 rich flue gas

Storage

Raw Material

Transport

CO2 Compression

Mixing gas

Exhaust air cleaning

Pre-heater

Raw Mill

Fuel Preparation

Fuel

CO2 Purification

Condenser

Rotary Kiln

Pre-calciner

Air In-leaks

Air

Rotary Kiln

Cooler Clinker

Oxidizer

Air Separation

Unit NGas Mixing

AirOxidizerUnit N2

2. Retrofitting boundaries

• Important aspect for the application of oxyfuel in Europe

• Retrofitting an existing burner for oxyfuel application is unlikely, but replacement by a suitable design is possible

• Designing a gas-tight two-stage cooler is feasibleDesigning a gas tight two stage cooler is feasible• False air intrusion could be reduced to the greatest

possible extent by overhauling/ replacing inspection doors and similar devices (< 6%)

• New safety and controlling devices necessary • Space requirements of ASU/CPU• Conventional behavior in trouble shooting restricted

(no opening of doors/flaps in the plant etc )(no opening of doors/flaps in the plant etc.)

Retrofitting is feasible

3. Impact on plant operation

• Air separation andCO2 purification areenergy intensive

• Influence on heattransfer andtemperature profiles gy

• Energetic integrationrequired

p p• Adaptation of plant

operation necessary

Gas Add. Plant Aggre-Property Aggre-gates

• New installations• Recirculation rate: F ti f t t l fl

Plant Modifica-

tionRecircu-

lation rate• Retrofitting existing

plantsFraction of total fluegas, which isreciculated to process

• Setting of oxygen level

tion

3. Impact of gas properties

Stress on2200 ∆ 50 - 100 C Stress on refractory

1800

2000

2200

tur [

°C]

n °C

1200

1400

1600

Gas

tem

pera

tem

pera

ture

i

1000

1200

Ofenlänge

G

∆ 150 C

Kiln length

Gas

te

Potential increase of

OfenlängeReferenz: Luftbetrieb Rezirkulierung, 21 Vol.-% O2Rezirkulierung, 25 Vol.-% O2 Rezirkulierung, 23 Vol.-% O2O2

O2O2

Reference: Air operationRecirculation Recirculation

Recirculation

Potential increase ofcoating formation

3. False air ingress and flue gas composition

87

88

Influencing parameters:

O

85

86

n flu

e ga

s [v

ol.%

] • Oxygen purity

• False air ingress

• Oxygen excess

83

84

2-co

ncen

tratio

n in • Oxygen excess

• Fuel type

81

82

1 2 3 4 5 6 7 8 9 10

CO

2

False air reduction of 6 - 8 % technicallyfeasible by improved maintenance withoutadditional sealing methods (like e.g. waste

air-ingress [% of flue gas]

Oxidizer: 95 vol.% O2, 3.5 vol.% O2 excess

Oxidizer: 98 vol.% O2, 3.5 vol.% O2 excess

Oxidizer: 99.5 vol.% O2, 3.5 vol.% O2 excess

g ( ggas flushed systems)

3. Flue gas recirculation

3100

3150Plant modificationsnecessary due to

3000

3050

3100

Ene

rgie

beda

rf g

Klin

ker

yreduced volume flow

in preheater

yde

man

din

ker

2900

2950

3000

Ther

mis

cher

Ein

kJ/

kger

mal

ene

rgy

in k

J/kg

cl

2850

2900

0,3 0,35 0,4 0,45 0,5 0,55 0,6

Rezirkulationsrate

T

Recirculation rate0.3 0.35 0.4 0.45 0.5 0.55 0.6

The

Fuel energy demand is depending on flue gas recirculation and treatmentD i i l ti t i l d l fl l

RezirkulationsrateRecirculation rate

Decreasing recirculation rate includes less flue gas losses

3. Energetic consideration

850

950

ker

650

750

850

kJ/k

g K

linke

r Power generationRaw material drying

in k

J/kg

clin

k

450

550

enth

alpi

e in

External heatexchanger

as e

ntha

lpy

i

250

350

0,3 0,35 0,4 0,45 0,5 0,55 0,6

R i k l ti t

Gas

0.3 0.35 0.4 0.45 0.5 0.55 0.6

Ga

Rezirkulationsrate

Abgas Vorwärmer Kühlerabgas, Stufe 2

Recirculation rate

Flue gas, preheater Cooler exhaust air

Recirculation rate determines the energy distribution andtherefore waste heat recovery potential

3. CO2 emission reduction potential

Capture rates of 88 to 99 % feasible Capture rate independent of recirculation rate Reduction of capture rate possible by

Exhaust gas of the CO2 purification unit (- 1 to 10 % capture) Additional firing for raw material drying (- 1 to 2 % capture) Leakage at cooler stage sealing (up to - 1 % capture)

RezirkulationRezirkulationRecirculation

Abluft von der CPUAbluft von der CPU

Exhaust gas ofCPU

Entsäuerung

Primärgas

CO2 zum Speicher

Kühl bl ft

Entsäuerung

Primärgas

CO2 zum Speicher

Kühl bl ft

Calcination

Primary gas

CO2 forstorage/reuse

BrennstoffKühlerabluft

mögliche Zufeuerung

BrennstoffKühlerabluft

mögliche Zufeuerung

FuelCooler leakagePotential additional

firing

4. Kiln operation – Impact on solid conversion

60

70

40

50

60

[wt.%

]

20

30

olid

con

tent

0

10

s

kil l thkiln length

Reference, C3S Reference, C2S

Recirculation 21 vol.% O2, C3S Recirculation 21 vol.% O2, C2S

Recirculation 23 vol.% O2, C3S Recirculation 23 vol.% O2, C2S

4. Limiting factors by quality and durability requirements

• No serious influence on clinker composition • Slight differences in cement properties

(caused by Fe2+) are in range of assured(caused by Fe2+) are in range of assured quality

• No negative influence on basic refractory material detectedmaterial detected

• Using non-basic materials an increasing thermo-chemical reaction expected

• Adaption of refractory brickwork necessaryp y y• Long-term test for evaluation advisable

14000

[49-442] Ca3SiO5[33-302] Ca2SiO4 / Larnite

[30-226] Ca2(Al,Fe)2O5 / Brownmillerite[38-1429] Ca3Al2O6 (cubic)

[32-150] Ca3Al2O6 (ortho)[45-946] MgO / Periclase

[37 1497] C O / Li

von unten nach oben:V1K1, 2011-i_MVT-03280V6K1, 2011-i_MVT-03285V11K1, 2011-i_MVT-03290V16K1, 2011-i MVT-03295

2000

4000

6000

8000

10000

12000

Abs

olut

e In

tens

ity

[37-1497] CaO / Lime[37-1496] CaSO4 / Anhydrite[46-1045] SiO2 / Quartz, syn

[49-1807] Ca5(SiO4)2SO4 / TernesiteP-2011/0372, A11/057 (Range 1)

V16K1, 2011 i_MVT 03295V21K1, 2011-i_MVT-03305V26K1, 2011-i_MVT-03310

No barriers expected from clinker quality and refractory

durability2Theta10.0 20.0 30.0 40.0 50.0 60.0

0

2000 durability

4. Impact on decarbonation

1

Increase of temperature level:

• Problems with 0,6

0,8

arbo

natio

n [-] Conventional

operation

burning low-calorific fuels in calciner may occur

0 2

0,4

degr

ee o

f dec

a ∆ 80 K

• Higher risk of coating formation in the calciner0

0,2

650 700 750 800 850 900 950 1000

d Oxyfuel operation

temperature [°C]

pCO2 = 0,2 bar pCO2 = 0,4 bar pCO2 = 0,6 barpCO2 = 0,8 bar pCO2 = 0,97 bar

4. Impact on cement properties

120 

105

110

Strenght developmentSetting behaviour

60

80

100

stre

ngth

in %

85

90

95

100

heat

in % %

20

40

60

com

pres

sive

65

70

75

80

85

hydr

atio

n

0

Standard condition Oxyfuel condition

2 days 28 days

60

65

Standard Conditions Oxyfuel ConditionsBurning: CO2/ Cooling:Standard Burning: Standard/ Cooling: CO2

samples 1 -5 after 48 h

Standard condition Oxyfuel conditionBurning: CO2/ Cooling: Standard Burning: Standard/ Cooling: CO2

Burning: CO2/ Cooling:Standard Burning: Standard/ Cooling: CO2

Testing at five clinker types of different reactivity No influence on chemical-mineralogical composition Cement properties are not influenced

5. Cost Estimation

New installation (2 mio tpy annual clinker capacity):

2030: 330 - 360 Mio € (Reference: 260 Mio €)

Investment costs

2030: 330 - 360 Mio € (Reference: 260 Mio €)

2050: 270 - 295 Mio €Remark: Costs for demonstration plant in 2020 would be significantly highersignificantly higher

Operational costsFixed operating costsRaw materials Misc

plus 8 to 10 €/tclinker on top of base casetransport and storage excluded

Coal

Power

Total cost increase of about 40 %

Additional costs per ton of avoided CO2 : 33 - 36 €/t CO2

6. Summary and Outlook

Oxyfuel technology in the cement clinker burning process technically feasible

Retrofit of existing plants is possible Cement properties are not impaired Optimum operational mode depends on local specification of the cement Opt u ope at o a ode depe ds o oca spec cat o o t e ce e t

plant (e.g. raw material moisture) Capture rate between 88 and 99 % Production costs are increased by 40% (excl transport and storage) Production costs are increased by ~ 40% (excl. transport and storage) Oxyfuel technology will not be available in the cement sector before

2030 ECRA CCS Project Phase IV.A is dealing with the further detailing of

previous phases and the concept study of an oxyfuel pilot plant

Thank you for the attention!

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